Soma Jawbone Frame B-Type

• The Jawbone B-Type frame is the perfect platform to build drop bar mountain touring and bike packing rig
• Tange Prestige heattreated butted CrMo steel; butted CrMo rear end
• IRD Broski Sliding Dropouts allows for running derailleurs as well as geared hubs like Rohloff (Stock dropout insert is for 135mm QR. 142 x 12mm ThruAxle inserts available separately, SF4958, SF4959. SF4960-142x12mm axle )
• IS mount disc brake tabs
• Front derailleur compatible (bottom pull)
• Headset for optional 11/8" matching fork: SHIS: ZS44/28.6 | ZS44/30. If running a tapered steerer fork, get an EC44 lower cup
• Rear rack and fender eyelets
• Two sets of bottle cage bosses; one set of cargo cage bosses on downtube
• 44mm headtube: Fits 11/8" steerer tubes and tapered steerer tubes with a headset swap
• 27.2mm post size/28.6mm frt. der. size/29.8mm seat collar, 73mm bottom bracket (English threads)
• Tire Width Range: 27.5 x 47mm to 2.6” / 700c x 38mm to 29 x 2.25”
• For matching fork please consider SF4030

Free bike shipping within the lower 48 states. Easy returns within 30 days.

Our rider support team can help with fit, setup, and the finer details.